从RFCO₃一次浸液中分离铁的工艺研究

Studies on the Technique of Separation of Iron from a Leaching Solution RFCO₃

摘要: 本试验以RFCO₃经氧化焙烧后用HCl浸后的一次浸液为原料，在各种不同的条件下，用N₂₃₅和TBP两种萃取剂，研究其对稀土中杂质元素铁等非稀土杂质的分离效果。试验结果表明：N₂₃₅的萃取效果要比TBP的萃取效果更好，在不同的萃取剂浓度和不同酸度的条件下N₂₃₅萃取稀土中铁效果可达90%以上，其最佳效果为99.56%；而在相同浓度N₂₃₅中分离铁的最佳酸度为c(H⁺) = 2.0 mol/L左右。但是从经济角度考虑，N₂₃₅的成本要比TBP高，在工业上TBP要比N₂₃₅应用更为广泛，故分离铁的最佳工艺，应该选用浓度为40%的TBP来萃取酸度为2.0 mol/L左右的浸液中的铁。

Abstract: In this study, RFCO₃ was oxidized and roasted, and then soaked with HCl for only once, and the immersion liquid was as a raw material. And the separation of non-rare earth impurities such as impurity elements in rare earth was studied under various conditions with two different extraction agents N₂₃₅ and TBP. The results showed that the extraction effect of N₂₃₅ was better than that of TBP, and the effect of the extraction of rare earth iron of N₂₃₅ was more than 90% under different extraction conditions and different acidity. The best effect was 99.56%. The optimum acidity of separation iron in the same concentration of N₂₃₅ is about c (H⁺) = 2.0 mol/L. However, from the economic point of view, N₂₃₅ costs higher than the TBP, and the TBP is applied more widely than N₂₃₅ in industry, so the best way to separate iron should be the concentration of TBP was 40% to extract the iron in the infusion which the acidity was about 2.0 mol/L.